And because of their sizes and orbits, the newfound planets are likely either rocky—like Earth—or watery, NASA scientists said. The two planets are located 1,200 light-years away in a five-planet system orbiting a star dubbed Kepler-62.

Called Kepler-62e and -62f, the planets "are by far the best candidates for habitability of any found so far," said William Borucki of NASA's Ames Research Center, the science principal investigator for the agency's Kepler Space Telescope.

"If you were on Kepler-62f and looking at the sun, it would be a little less yellow than ours," said Borucki, whose announcement coincided with the release of a study on the topic in the journal Science.

"And at sunset the sky would be more red. But otherwise it would basically look and feel the same," he said.

"I would call this a breakthrough discovery."

The press conference also introduced another study released today in the Astrophysical Journal, which involves a related discovery of a sun very much like our own named Kepler-69.

Exoplanet Hunters

The newly found extrasolar planets, or exoplanets, are part of a vast menagerie of celestial bodies discovered in recent years. Our Milky Way galaxy alone is now known to have hundreds of billions of planets circling its stars.

Exoplanets that are Earth-size, are rocky or watery, or that exist in habitable zones in relation to their suns have all been found before. But the two new planets are the first that appear to meet all three criteria, Borucki said.

Although these planets are now believed to be habitable, Borucki cautioned there's no evidence that they actually support life.

The planets were found by the Kepler Space Telescope, an orbiting observatory that studies 170,000 stars and the planets that circle them in a small, distant patch of the Milky Way. It works on the understanding that if an exoplanet crosses in front of its sun, the light from the star will slightly dim; this shows researchers there's a planet in orbit around that star.

Those early discoveries overturned a lot of assumptions about how solar systems could be organized, since the prevailing understanding had been that other solar systems resembled our own. That was why finding a Jupiter-like planet in the place where Mercury or Venus would be in our solar system was unexpected.

But as Kepler enters its fourth year of observing its selected stars, it is able to detect smaller planets with orbiting periods much longer than those found earlier in the mission.

So far Kepler scientists have identified 350 Earth-size exoplanets. The two planets introduced today—called "super Earths"—are 1.4 and 1.6 times larger than Earth, and orbit around their sun in 122 and 267 days, respectively.

In Search of Super Earths

There's some debate in the exoplanet community about what constitutes an Earth-size planet. But Kepler has also found planets that are Mars-size—about half the diameter of Earth—and even moon-size.

"There's been a steady progression in the field from easier-to-find planets to harder-to-find planets," said Kepler team member Geoff Marcy of the University of California, Berkeley.

"Our goal is to find a extrasolar planet that is within 5 percent [the size of] Earth."

The question of whether or not the planets are solid, liquid, or consist largely of gas is more complex and not easily teased out using the Kepler's method of tracking planetary transits.

Borucki said the team's conclusion that Kepler-62e and -62f are not gas planets but rather potentially habitable rocky or water planets is based on their size and place in the Kepler-62 planetary system. No planet the size of Kepler-62f has ever found to be gaseous, he said.

So far that method has not been effective for planets as small and as distant as those around Kepler-62. But Marcy said his team, based at the W. M. Keck Observatory in Hawaii, will be working to better understand the density of the newfound planets.

New Sun Discovered

Scientists also described another recent discovery: Kepler-69. It's "the sun most like our own that we've found that has a planet orbiting in the habitable zone," said study leader Thomas Barclay, a Kepler scientist at the Bay Area Environmental Research Institute in Sonoma, California.

He said planets orbiting hot stars like our own are more difficult to detect than those circling cooler stars, so the discovery of Kepler-69 is a sign of major technical progress.

"We're finding planets now that were unimaginable not very long ago—small ones pretty far from their stars, and now with very bright suns," Barclay said.

"Moving Moment"

Marcy, a co-author of the Kepler-62 study, called the new exoplanet discoveries "profound."

He said he didn't think the importance of the Milky Way discovery has really sunk in with the public.

"It's not just that most stars have Earth-sized planets, but some of them—many of them actually—are at a distance from their suns that allow for lukewarm temperatures," Marcy said. "That means they just might support life."

He added, "It's a very moving moment in humanity's efforts to understand our home planet and the possibility of other habitable planets in the universe."

Impressive. The notion of this discovery, correct or false, is simply amazing. As humans, we should be proud of these men and women in these areas of science, who are doing so well at discovery and exploration. Yet, space is a far reaching exploration project that will not be fully conceived for many centuries to come. It seems we have placed space as the next frontier, while we have yet... yet to fully understand our own planet and solar system. We as humans seem to think that discovery outside of understanding is concise with scientific research, yet mathematics create what our eyes cannot see. Whereas many of these photographs are actually imagined rather than rendered by sight, the ideas are astonishing and perhaps truth to a weary explorer reading temperature graphs and wobbles. We can really only imagine the possibility, not grasp it. A second earthly home is possibly obtainable in the future, but for now it is only a gasp of dreaming from tedious distant views. We shall need to conquer humanity, and change the course of our path here on this planet first before we set sights on distant glittering planets that might support human life, for who are now, is not deserving of a new home.

Exoplanets that are Earth-size, are rocky or watery, or that exist
in habitable zones in relation to their suns have all been found
before. But the two new planets are the first that appear to meet all
three criteria, Borucki said

So it is time to start a new religion.. The Church of infinite worlds.
Kind of makes sense that when you die, your "soul" or "life force" or
what makes you "you" goes to an alien life form. Since there obviously
is an infinite amount of planets only makes sense that there is life on
some of them. Also kind of makes sense that is why there is a speed of
light barrier. This way it keeps everyone apart. Also kind of makes
sense in the view of "Heaven and Hell" there has been some overlap where
people have been incarnated in really great planets, and some not so
much, and sometimes have come back to here then told about good or bad
experience's. Also kind of makes sense in regard to the Buddhist
religion. Hmmm food for thought eh??

Exoplanets that are Earth-size, are rocky or watery, or that exist in habitable zones in relation to their suns have all been found before. But the two new planets are the first that appear to meet all three criteria, Borucki said

This is nonsense ! there is only one star called "Sun" like one "Sirius" etc...

Remember that the definition of "habitable" currently used by the astronomical community when referring to exoplanets means only that it's at a distance from its star where temperatures could exist at its surface that would allow the existence of liquid water (if all other conditions were right), not that it would necessarily be habitable by humans. For example, a planet at a distance from a substantially bluer, hotter star than the Sun that would allow liquid water, would receive a concentration of high-energy radiation from that star that would not be healthy for unprotected humans. Conversely, a planet at a distance from a substantially redder, cooler star than the Sun that would allow liquid water, would likely not receive energetic enough light for the growing of most food crops we're used to, and it would likely be a pretty gloomy place, only dimly lit during the day.

Even if we know for certain that a planet's star is too blue or too red to host a planet suitable for human colonization, if the planet is at the right distance for liquid water to exist, it will be called "habitable" in science magazine articles.

This is mind blowing. I'm actually very impressed with this find.. 1200 light years is no piece of cake! Lets take a step back and analyse the following challenges.

1. How the hell are we going to get there? saying we can develop the technology and ACTUALLY developing it are two different things..I cant even download sushi straight from my laptop to my desk. is that the technological mind set that would get us 1200 light-years on our way to colonizing a distant planet?

2. Lets say we do find ourselves on Keplar 62f, what kind of environment are we hoping to meet? And how would long term exposure to this new environment affect our average life span, our biology, chemistry etc. i mean its one thing analyzing from afar, but when you juxtapose our Earth with another "possible habitat", we may be surprised to discover that this new world would be totally different from ours..

3. Does it have enough oxygen? What kind of Bio-diversity are we hoping to find there and how are they structured to adapt?. How do we hope to adapt?

4. Funds. A project like this would certainly create a gaping hole in the worlds economy. One country surely cant bear the burden of putting in place all the resources required because resources needed to ACTUALIZE this kind of thing usually pulls together 3 or more world powers. In other to sustain this project in the shortest amount of time, other aspects of economic preservation would plunge into the ground. Are we not currently in a recession?

5. Politics and science some times have differing goals. Not many people in top places would support this aspiring idea. This project may not even see the light of day.

6. Time! At least Three generations would have gone by before this project scratches the surface. Even with all the technological advancement we are experiencing today, we still have a long way to go. It would be nice to live in a time when Humans went on vacation to other planets.

Our next task is to get to the planets before we either destroy this planet through pollution/war or disease. Its nice to find these planets but we have to get there. It is going to take a global effort to create the technology needed to explore the universe but it is a step the human race is going to have to make in order to survive.

A number of commenter’s seem convinced that these potentially Earth-like planets could just as easily be Venus-like or Mercury-like. That is pure poppycock! The "conjugate diameter" (generalized version of a "diameter" necessary when describing ellipses that are not "perfect circles," since only a circle has a constant diameter) of a planets orbit from it's star plays a tremendous role in it's surface conditions. The shift from solid body planets to "gas giants" as the distance from the sun increases is evidence of this. The distance of these newly discovered planets from their sun makes it extremely unlikely (nearly impossible) that they have "Venus-like" surface conditions.

Before you go espousing criticisms, claiming that Planetary Scientists (who have dedicated their lives to the study of this topic) are making brash and unfounded assumptions, you should take a few minutes to familiarize yourself with the most basic theories of Planetary Science.

In this case, you are the ones making unfounded assumptions, not the scientists who have spend close to a decade in school researching this subject. If you were to follow the example set by these scientists, you too could comment on this discovery without sounding like a complete idiot.

Any clues as to the shape of these planets' orbits: nope. Any clues as to how stable the planetary system is: nope. Any reason to believe that these planets are not more SuperVenuses: nope.

These planets are interesting in their own right, and their discovery is a credit to the Kepler mission. But why tarnish the discovery with the same old one-dimensional analysis that is obsessed with finding space boogiemen.There is plenty of life to discover right here on Earth. No need for the media to throw a Mexican wave every time another supposedly "earthlike" planet is discovered.

Any clues as to the shape of these planets' orbits: nope. Any clues as to how stable the planetary system is: nope. Any reason to believe that these planets are not more SuperVenuses: nope.

These planets are interesting in their own right, and their discovery is a credit to the Kepler mission. But why tarnish the discovery with the same old one-dimensional analysis that is obsessed with finding space boogiemen.There is plenty of life to discover right here on Earth. No need for the media to throw a Mexican wave every time another supposedly "earthlike" planet is discovered.

According to the New Message from God, the universe is replete with intelligent life. Humanity is coming into contact with other civilizations. This presents grave dangers and great opportunities. Welcome to the greater community, Earthlings!

I wonder what the next step is. Are we able to discover any more information from this planet? Will we ever be? What are the main uses of knowing these planets exist, other than having a better understanding of the formation of solar systems? Are we stuck with seeing life becoming more probable on other planets, but not being able to prove it unless by finding life on planets from our own solar system?

May be Einstein discovered mass-energy conversion for this. Very easy to produce energy from a radio-active material. Energy generation should be possible with any matter with higher cost at higher temperatures.

That should give us enough energy to change earth's orbit and reach out close to the distant earth-like planet to an orbit around a new star, say kepler62, so you can jump easily to kepler 62e. Confused? Read again :-)

@Hubert de Souza Dude, the term "sun" refers to the star that the planet in question is orbiting. We call our sun "The Sun" because we're self centered, not because that's the only thing that makes sense.

@Gradivus Graham Well, first of all the literal definition of a habitable planet means that "it is a life supportive planet". Our planet Earth IS in the habitable zone and the planets they've discovered are in the habitable zone. Scientists have calculated the accurate range of the habitable zone within the solar system of a star even with a smaller white dwarf star and they've calculated the habitable zone of Kepler-62 in analogy to our Sun's. So regardless of the size or temperature of a star there would always be a range of habitability surrounding it.

The habitable zone in a star's solar system can gradually change such as our Sun's habitable zone can move sooner to Mars or even Jupiter's moon, Europa in millions of years when our Sun will be in the process of going to the red giant phase.

If liquid water exists on a rocky planet or moon it will ALWAYS host or sustain life as it is EVIDENT on our planet and especially if a rocky planet is on the habitable zone for millions or billions of years which would have fully developed its life-friendly atmosphere.

@Cynthia Anochikwa You missed perhaps the biggest question. Just like the movie where the invading aliens were conquered not by humans but the common cold virus, even if these planets were habitable, with all the atmospheric formalities we need to be able to sustain our lives with, we would need to be able to survive those planets most smallest native species, bacteria and viral infection.

@Cynthia Anochikwa Indeed. The seeds of life are the best we can hope to attempt for a long time. A robotic mission with frozen single cell life and bacteria that takes tens of thousands of years to reach it's destination and has unpredictable chances of starting life assuming it's not already started and better adapted than what we send.

@Bill Doyle As long as any attempt at global cooperation is hampered by the "world government conspiracy crowd" or just by nations still unwilling to divert defense spending, we'll not have the dedicated drive to create the technology. Profits won't drive it, because the payoff is too long term.

@Bill DoyleIf we can develop the technology to travel to and colonize a far distant
planet than we can develop the technology to save Earth. Giving up and
shipping off is a cowardly cop-out. I'm all for the exploration and,
maybe, eventual habitation, but giving up on our Home is not the answer.

@Matthew Zaikowski There are many reasons that planets turn out the way they do. In our solar system are a wide variety of atmosphere types and we don't even know how these formed. It is pretty silly to say that you have confidence that these planets have earth-like atmospheres just because they fall within a Goldilocks zone.

In fact, it is not at all understood why Mars has virtually no atmosphere. To assume that a planet that you cannot even see has a stable atmosphere like earths is unfounded. Some direct measurements are needed to make that claim.

@Gustavo Maciel If it brings reality to the situation, we could send a message which travels at the speed of light and if intelligent life is there and listening then we only have to wait "2 4 0 0" years for a handshake response :). Na unless we figure out a faster than light method of travel were just stuck here never knowing.

Traditionally, the next step is rational criticism leading to skepticism followed by dismissal as the media lurches onto the next sensationalist "discovery".

Nevertheless knowing that exoplanets exist, and in systems radically different to our own, provides strong support to the rare earth hypothesis as we come to realise what a unique planet the Earth is.

There is still no evidence that "life is becoming more probable on other planets", at least none within detection range. Kepler has searched long and hard, yet the more of these toxic planets and unstable systems it finds, the LESS probable life in space becomes.

Traditionally, the next step is rational criticism leading to skepticism followed by dismissal as the media lurches onto the next sensationalist "discovery".

Nevertheless knowing that exoplanets exist, and in systems radically different to our own, provides strong support to the rare earth hypothesis as we come to realise what a unique planet the Earth is.

There is still no evidence that "life is becoming more probable on other planets", at least none within detection range. Kepler has searched long and hard, yet the more of these toxic planets and unstable systems it finds, the LESS probable life in space becomes.

While our understanding of these worlds will obviously be limited (for the foreseeable future) by our vast distance apart from them, my understanding is that we should be able to analyze the light spectra from these worlds to better understand their composition, which could perhaps tell us more about their habitability and the posibility of life.

Uh,
just because radioactive material produces energy does not mean that it
produces anywhere near enough energy to accelerate even a small amount
of matter to even a hundredth of the speed of light (if that were
plausible then it would only take 120,000 years for that matter to reach
the solar system in question.)

I cannot imagine where you got
the idea of that "changing the earth’s orbit" would be possible and how
doing so would permit interstellar travel? First of all, if we were to
change our orbit, once we left the "goldilocks zone" around the sun,
all life on earth would be eradicated. Also, changing the orbit would
not result in the earth travelling close to light speed, meaning it
would take longer to reach a new solar system than humans have existed.

It sounds like you might be the one who is confused. You should read this short summary of a seminal paper by Nobel Prize Winning Physicist Edward Purcell.
Purcell pointed out seemingly insurmountable hurdles in achieving
interstellar travel, most of which were rooted in some of the most
fundamental properties of physics. I'm not saying that it is
impossible. Only a fool would think that our current understanding of
the nature of the Universe is complete enough to rule out the
possibility. The flip side of that coin is that the current models in
Theoretical Physics are no where near complete enough to derive a
feasible method for near light speed (let alone faster than light speed)
travel.

@Dee Smith Even with new propulsion systems being tested and devised for travel in space? Although we are lightyears away from implementation, the possibility is profound. We could travel someday at the speeds needed to reach these planets in much less time than we can now.

Days ago i found in Internet the follow phrase "I can see only a better world on the ashes of this one" for me this have a deeper sense. May be it will be never happend we explore or colonize other Planets and maybe this should never happend if we look how we handle our own planet, so it would be better we spend the money in recover our own Earth and clean it from the ones who destroy it for their own profit.

@Brendan Harrigan@Bill Doyle I totally agree with you and giving up is not something I am prone to however there are people on this planet who have or will have shortly weapons of immense power. The leaders of these countries have shown they are not rational. So yes, although we have the capability/technology to save ourselves, that does not mean that we can come together and actually do it.

@Brendan Harrigan While I agree with what you said it wouldn't hurt to have a back up planet or two to go too. In the event something man couldn't stop ie: Another planet/super massive asteroid on a collision course with us, something goes extremely wrong with the sun, etc. No matter how advanced we become there will always be things we are just to small to fix.

@Evan Neumann Yes Matt you are correct we can't know much about these planets. I think it is known however why Mars has virtually no atmosphere. It's related to it's low density and therefore lack of it's core still spinning and creating a magnetic barrier against solar winds. But then again that's off memory and Merlot may be affected my memory :)

First of all, thanks a lot for understanding the though of moving the Earth and not ruling out this option with the current understanding of Nature.

I am a Software Engineer by profession and had never been associated with Astronomy in my career. But I often think about two things - how universe formed and how come there exists life!! So, apologies if I had made foolish comments - I just put whatever was there in my mind, because I had no body to discuss this with.

Yes, I missed the simple point that we will be out of "goldilocks zone" on the way. Not sure how we should protect ourselve :)

Also, yes, I agree we have not advanced enough understanding the Nature.

I was not imagining fuel in tons but in trillion trillions of tons. At least some part of earth should be able to make it, after spending part of the Earth as fuel.

The speed - will be no where comparable to the speed of light - so again - millions of years.

This is not practically feasible with the current understanding of nature and the technology we have and the discoveries we made. How do we generate energy of the order of m*C*C from insignificant non-radioactive matter? No clues yet :)

I believe that need is the mother of invention. Inventions that involve great risk are rarely made, unless otherwise we will be at risk.

Thanks for the link, and I now agree that "interstellar space travel is "nonsense"", as you said with the current understanding of the Nature (ie., E=m*C*C). I highly respect Einstein and his contributions, but never know a new scientist can discover something more efficient way than E=m*C*C. (What was our belief on Energy generation before Einstein equation?)

Here is my question

if some large meteorite with size of the order of moon/earth is going to come close to earth, and our calculations prove that it is definitely going to hit the Earth, what do you think is the way out? Let us say, we have a 100 years for this event to happen (Assume we have technology enough to precisely calculate this event). What do you think is the way out that we can protect mankind?

@Bill Doyle@Jon Mackinnon@Brendan Harrigan Nature and evolution (on this planet) have a way of solving these types of problems. I tend to think intelligence is a favored attribute in life and therefore some version of us or life will prevail for a long time. At least that's my glass half full notion.

@Jon Mackinnon@Brendan Harrigan This is actually a very good point. You never want to put all your eggs in one basket and while that may be over simplifying, if this basket get dropped were in big trouble.

Also, we will eventually use all available resources on this planet and probably pollute it to death. Now, I could never be called as an environmentalist, its still pretty obvious that that we will never fully embrace technologies that won't pollute our water and air. We need to colonize other planets, we are running out of room here. Its kind of scary when you think about it.